芳胺常压气相N－烷基化反应研究

在固定床催化反应器中常压下研究了芳胺和醇的气相法Ｎ－烷基化反应。考察了γ－Ａｌ２Ｏ３系列催化剂的反应性能，筛选出了两种适用于苯胺Ｎ－甲基化反应且性能较好的催化剂。反应条件为：在甲醇和苯胺的摩尔比为３１时，反应温度为２８０℃，液时空速为０．３ｈ－１的条件下，苯胺转化率为９９％，生成Ｎ，Ｎ－二甲基苯胺（ＤＭＡ）的选择性为９２％。研究了甲醇和芳环上不同位置取代的甲基苯胺的反应规律，其转化率顺序：苯胺≈对一甲苯胺≈间－甲苯胺＞邻－甲苯胺。从Ｃ１到Ｃ４不同结构的醇和苯胺反应的规律研究，证明随醇中碳原子数目的增加，醇的反应活性降低，正构醇和苯胺反应和异构醇与苯胺反应随温度升高的变化趋势相反。     

芳胺常压气相N—烷基化反应研究

在固定床催化反应器中常压下研究了芳胺和醇的气相法Ｎ－烷基化反应。考察了γ－Ａｌ２Ｏ３系列催化剂的反应性能，筛选出了两种适用于苯胺Ｎ－甲基化反应且性能较好的催化剂。反应条件为：在甲醇和苯胺的摩尔比为３：１时，反应温度为２８０℃，液时空速为０．３ｈ＾－１的条件下，苯胺转化率为９９％，生成Ｎ，Ｎ－二甲基苯胺（ＤＭＡ）的选择性为９２％。研究了甲醇和芳环上不同位置取代的甲基苯胺的反应规律，其转化率顺序：苯胺     

Mg的添加对Mo／ZSM－5催化剂催化甲烷芳构化性能的影响

 通过XRD，N2吸附和吡啶FT－IR等方法考察了Mg的添加对Mo／ZSM－5催化剂物化性质的影响．吡啶FT－IR结果表明，Mo－Mg／ZSM－5催化剂上Lewis酸中心与Br¨onsted酸中心的比值随着Mg添加量的增加而增大．在甲烷芳构化反应中，虽然催化剂上的积碳量随着Mg含量的增加而减少，但只有6％Mo－0．75％Mg／ZSM－5催化剂表现出比6％Mo／ZSM－5催化剂更好的稳定性，6％Mo－2％Mg／ZSM－5和6％Mo－3％Mg／ZSM－5两个催化剂的稳定性均比6％Mo／ZSM－5催化剂差．根据催化剂稳定性与酸性的关系提出，在有足够Br¨onsted酸中心存在的前提下，可以通过调变Lewis酸中心和Br¨onsted酸中心的比值来提高催化剂的稳定性．     

气相法苯胺N-烷基化反应研究Ⅲ.苯胺和甲醇催化合成N,N-二甲基苯胺研究

本文报导了在系列复合氧化物催化剂上苯胺和甲醇反应合成Ｎ，Ｎ－二甲苯胺（ＤＭＡ）研究，并从中选择了活性和选择性都良好的ＬＨＰ催化剂，在常压气相反应条件下详细地考察了反应温度，液时空速（ＬＨＳＶ），苯胺和甲醇摩尔比变化等对催化剂活性和选择性的影响，提出了两段转化的新工艺流程。并经扩大试验，证明两段转化工艺过程优于一段转化法。第一段反应时苯胺转化率大于９５％，ＤＭＡ选择性大于７０％，第二段转化后，产物中几乎不含苯胺，ＤＭＡ选择性大于９４％，并在工业固定床催化反应装置中常压气相反应条件下试生产成功。     

改性纳米ZSM－5催化剂脱除汽油中烯烃的性能

 在考察ZSM－5沸石晶粒大小对脱除汽油中烯烃的影响的基础上，用纳米ZSM－5沸石作为活性组分负载Co－Mo氧化物制备了改性纳米ZSM－5沸石催化剂，并用XRF，NH3－TPD和TEM等方法对催化剂进行了表征．以脱除DCC汽油中的烯烃为探针反应，临氢条件下，在固定床反应器上对催化剂脱除烯烃的性能进行了评价，考察了反应温度、压力、质量空速和氢／油比对催化剂脱除烯烃性能的影响．结果表明，由于纳米ZSM－5沸石具有晶粒小、微孔短、扩散路程短以及表面酸中心数量多等特点，因而表现出较高的催化活性和较强的抗积碳性能．在V（H2）／V（oil）＝300，WHSV＝3h－1，p（H2）＝3．0MPa和θ＝350℃的适宜条件下，DCC汽油中烯烃的含量由60．7％下降到40％左右，芳烃和烷烃的含量增加；在脱除烯烃的同时可维持汽油的辛烷值不降低．催化剂连续运行1000h以上，其脱除烯烃的性能稳定．     

含铜MFI分子筛的H2-TPT和O2-TPD研究

 采用H2－TPR和O2－TPD手段考察了不同金属离子交换的ZSM－5分子筛催化剂上的氢还原性能和氧脱附性能．发现Cu－ZSM－5催化剂的储氧能力及氧脱附性能优于Co－ZSM－5和Fe－ZSM－5催化剂;储氧能力强、低温下氧脱附性能好的催化剂,对NO分解反应的催化活性就高．铜离子是反应的活性中心．添加Ag和Ce可使Cu－ZSM－5催化剂上氧的脱附温度大大降低．Cu－ZSM－5／堇青石整体式催化剂上Cu的存在形式与单纯的Cu－ZSM－5有差异,整体式催化剂上的一价铜数量少,但较稳定．     

以环己胺为模板剂的ZSM－35分子筛的合成及其催化性能

 采用环己胺为有机模板剂成功地合成出ZSM－35分子筛．反应釜的转速对ZSM－35的晶化过程有明显的影响．NH3－TPD结果显示ZSM－35的酸性分布与ZSM－5分子筛类似，但ZSM－35具有强于ZSM－5的酸性中心．酸碱浸泡试验及热分析结果表明ZSM－35具有良好的耐酸碱性和热稳定性．在连续流动的固定床反应装置上，将担载少量镍的ZSM－35分子筛催化剂用于催化裂化汽油的加氢异构化反应，结果表明，Ni／ZSM－35催化剂可降低汽油中的烯烃含量，增加异构烷烃和芳烃的含量，从而提高汽油的质量．     

气固相法合成的Ti-ZSM-5催化剂上苯乙烯氧化反应的宏观动力学

 采用TiCl4气固相同晶取代法制得的Ti－ZSM－5作催化剂,对H2O2氧化苯乙烯反应的宏观动力学进行了研究,考察了催化剂、苯乙烯和H2O2用量及反应温度对苯乙烯氧化反应速率的影响．结果表明,催化剂Ti－ZSM－5和底物苯乙烯对苯乙烯氧化反应速率的贡献均为一级,而H2O2为1／2级;苯乙烯氧化反应的表观活化能Ea＝48．14kJ／mol．当以丙酮为溶剂,在n（PhCH∶CH2）／n（H2O2）＝7．91,催化剂用量为20g／L,反应温度为343K的条件下,反应360min时,苯乙醛选择性和H2O2利用率分别可达91．9％和88．6％．     

Mo/ZSM-5催化剂体系上NO的选择性催化还原研究

 首先用浸渍法在HZSM－5上负载了不同的金属元素（Mo，Sn和Ni），并比较了它们在含氧条件下对NO分解反应的影响．结果表明，Mo／ZSM－5的催化活性最高．进一步用离子扩散法、浸渍法、物理混合法及合成法制备了四种Mo／ZSM－5样品，并以NH3为还原剂，考察了它们的NO的选择性催化还原反应性能．结果表明，用离子扩散法制得的样品对NO还原反应的催化活性最高，在360℃下，NO转化率可达98％．同时，用XRD，SEM，ICP和EDS等技术对4种样品的体相和表面结构进行了测试．结果表明，用离子扩散法制得的样品，Mo元素在分子筛催化剂的内表面有很好的分散性，导致Mo／ZSM－5具有高的催化活性．这可能是由于Mo元素迁移到分子筛的孔道内，在催化剂表面形成了有利于NO选择性催化还原反应的某种特殊活性结构．     

ZSM－5（核）／AlPO4－5（壳）双结构分子筛的合成与催化裂化性能

 采用X射线衍射、扫描电镜、X射线能量散射谱、红外光谱和核磁共振等多种物化方法对合成的ZSM－5（核）／AlPO4－5（壳）双结构分子筛进行了表征，证明这种材料具有以ZSM－5为核层、以AlPO4－5为壳层的双结构特征．考察了合成条件对ZSM－5（核）／AlPO4－5（壳）分子筛形貌的影响，发现ZSM－5分子筛的加入方式对产物的形貌有较大影响．重油裂化反应结果表明，ZSM－5（核）／AlPO4－5（壳）双结构分子筛的催化性能比ZSM－5和ZSM－5／AlPO4－5机械混合分子筛样品好，表现为原油转化率和低碳烯烃、汽油及柴油收率提高．     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.     

Chemistry of heterocyclic compounds at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, over 50 years (Review)

The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.     

Sulfur-directed metal-free and regiospecific methyl C(sp3)–H imidation of thioanisoles

Regiospecific and direct imidation of the methyl C(sp³)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.     

Selective syntheses of 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones via temperature-dependent Rh(II)-carbenoid-mediated 2H-azirine-ring expansion

The Rh(II)-catalyzed reaction of 2-carbonyl-substituted 2H-azirines with ethyl 2-cyano-2-diazoacetate or 2-diazo-3,3,3-trifluoropropionate provides an easy access to 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones. These compounds can be selectively prepared from the same starting material using temperature as the only varied parameter. The 2-azabuta-1,3-diene intermediate, a common precursor for both heterocyclic products, isomerizes into 2H-1,3-oxazine under kinetic control, while 1H-pyrrol-3(2H)-one is the sole product of the reaction at elevated temperatures. According to DFT-calculations a one-atom oxazine ring contraction involving ring-opening to a 2-azabuta-1,3-diene intermediate, followed by a 1,5- and 1,2-prototropic shift leads to the consecutive formation of imidoylketene and azomethine ylide, which then further undergo cyclization to the pyrrole derivative.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.